Conversion of high-boiling hydrocarbon oils into lower boiling hydrocarbon oils



Aug. 1, 1933. w. E. WARWICK 1,920,331

CONVERSION OF HIGH BOILING HYDROCARBON OILS INTO LOWER BOILING HYDROCARBON OILS Filed Nov. 9, 1925 Orawo/f -P/ oe C017 Fatented Aug. 1, 1933 UNITED STATES PATENT OFFICE CONVERSION OF HIGH-BOILING HYDRO- CARBON OILS INTO LOWER BOILING HYDROCARBON OILS William E. Warwick, Chicago, 111., assignor to Standard Oil Company, Whiting,'Ind., a 001'- poration of Indiana The present invention relates to improvements in the conversion of high boiling hydrocarbon oils into lower boiling hydrocarbon oils, such, for example, as gasoline or motor fuel. It will be fully understood from the following description illustrated by the accompanying drawing, in which apparatus suitable for carrying the invention into effect is illustrated diagrammatically.

Referring more particularly to the drawing, the numeral 5 indicates a furnace setting in which is mounted a coil 6 of any suitable commerical construction. The oil to be converted is supplied to the coil 6 through the inlet line '7. Heated oil leaving the coil 6 passes through the line 8 into an enlarged chamber 9 which is preferably lagged with suitable insulating material, as shown diagrammatically at 10. In the enlarged chamber 9 vaporization may take place, the evolved vapors passing out through the vapor line 11 into the lower portion of a suitable dephlegmator 12. In the dephlegmator, the vapors of products heavier than the desired distillate products are condensed, the condensing action being suitably aided, if desired, by the passage of a cooling medium through the coil 13 in the upper portion of the dephlegmating tower. Any other suitable method of obtaining a reflux cooling action may be employed, for example, the introduction of charging stock or other suitable hydrocarbon oil directly into the dephlegmator 12; The uncondensed vapors pass out of the dephlegmator 12 through line 14 to any suitable condensing and pressure maintaining devices (not shown).

Reflux condensate formed in the dephlegmating tower 12 may be withdrawn therefrom through the line 15, and, if desired, may be forced, as by surge pump 16,,through line 17 to the inlet 7 of coil 6.

In connection with the enlarged chamber 9, an auxiliary heating system is provided. In the form illustrated in the drawing, an oil conduit 18 leads from the lower portion of the chamber 9, at a point substantially remote from the connection of the line 8 to the chamber 9, to a heating coil 19 mounted in asuitable furnace setting 20. From this coil the oil passes through a conduit 22 to a higher point in the enlarged chamber 9, the point of connection of the line 22 being substantially remote from the points of connection of the lines 8 and 18. If desired, a suitable pump, as a surge pump 23 may be provided in the line 18 to aid the circulation of the oil through the heating coil 19.

In accordance with the present invention, the

oil to be converted, which may suitably be a high boiling hydrocarbon oil of the nature of gas oil, or a'heavier oil, if desired, is forced through the inlet 7 into the coil 6 in which it is heated to conversion temperatures, and at a velocity to prevent substantial deposition of carbonaceous matter such as coke or the like, the pressure maintained thereupon being suflicient to keep the unconverted oil substantially in liquid phase, say above 4 atmospheres. From the coil 6, the oil, heated to a temperature above 700 F., for example, 775 to 825 F.'passes through the line 8 into the enlarged chamber 9, in which a further conversion of the oil to a substantial extent takes place under pressure above 4 atmospheres. Residuum may be withdrawn from the chamber 9through the valved draw-01f line 24, this withdrawal taking place either continuously or intermittently, as desired.

The unvaporized liquid in the chamber 9 is withdrawn through the line 18 and passes through the heating coil '19 and returns to the chamber 9 through the line 22. By this means, the oil in the chamber 9 is maintained at conversion temperatures approximating the temperature at which the oil enters the chamber 9 from the coil 6, or even slightly higher. In the coil 19 the oil is only moderately heated, and no substantial deposition of carbon takes place therein. Thus, the heating of the oil in the coil 19 is preferably controlled to maintain the temperature of the unvaporized residuum in the chamber 9 at substantiallythe same temperature at that at which the oil leaves the coil 6, or at most, not more than 50 to 100 thereabove.

A relatively small amount of conversion, say not over 10%, is effected in the coil 6. The oil is retained'in the enlarged chamber 9 at the temperature therein prevailing for a period to permit a substantial further conversion into gasoline-like products, such additional conversion amounting to from 19 to 30% or even higher. The total conversion may be from 20 to 69% in a suitable operation of the present invention.

The vapors evolved from the oil in the chamber 9 pass through the vapor line 11 into the dephlegmator 12, in which products heavier than the desired distillate are condensed, the condensing action being aided by the passage of a cooling medium through the coil 13. This cooling medium may suitably be a hydrocarbon oil heavier than gasoline, and may subsequently be supplied to the system as a part of the stock to be cracked therein. The reiiux condensate formed in the dephlegmator 12 is withdrawn through the line 15 by pump 16 and may suitably be forced to the inlet 7 of the coil 6, mingling therein with the fresh stool: charged into the still.

I claim:

1. The method of converting high boiling hydrocarbon oils into lower boiling hydrocarbon oils which comprises passing such oil in a flowing stream through a heated zone in which the oil is heated to conversion temperatures above 700 F. under pressure, discharging the heated oil into an enlarged chamber in which further conversion of the oil takes place with superatmospheric pressure maintained thereupon, and maintaining s the unvaporized oil in said chamber at a conversion temperature by passing portions of it in an independent flowing stream through an independent heating zone and back to said chamber in an independent stream at a point substantially remote from the point of introduction of oil from said first named heating zone.

2, The method of converting high boiling hydrocarbon oils into lower boiling hydrocarbon oils which comprises passing such oil in a flowing stream through a heated zone in which the oil is heated to conversion temperatures above 700 F. under superatmospheric pressure, discharging the stream of heated oil into an enlarged chamber at a predetermined point, in which chamber further conversion of the oil takes place with superatmospheric pressure maintained there upon and maintaining the unvaporized oil in said chamber at a conversion temperature by withdrawing it from said chamber, passing the withdrawn oil in a flowing stream to an independent heating zone, and returning it to said chamber at a point substantially remote from the point at which the heated oil is introduced from said first named heating zone. a

3. The method of converting high boiling hydrocarbon oils intoslower boiling hydrocarbon oils which comprises passing such oil in a flowing stream through a heated zone in which the oil is heated to conversion temperatures above 700 F. under superatmospheric pressure, discharging the stream of heated oil into an enlarged chamber at a predetermined point, in which chamber further conversion of the oil takes place with superatmospheric pressure maintained thereupon, and maintaining the unvaporized oil in said chamber at a conversion temperature by withdrawing it from said chamber at a point substantially remote from the point at which the said heated oil is introduced into said chamber, passing the withdrawn oil in a flowing stream through an independent heating zone, and returning it to said chamber at a point substantially remote from the point at which the heated oil is introduced from said first named heating zone.

4. The method of converting high boiling hydrocarbon oils into lower boiling hydrocarbon oils which comprises passing such oil in a flowing stream through a heated zone in which the oil is heated to conversion temperatures above 700 F. under superatmospheric pressure, discharging the stream of heated oil into an enlarged chamber at a predetermined point, in which chamber further conversion of the oil takes place with superatmospheric pressure maintained thereupon, and maintaining the unvaporized oil in said chamber at a conversion temperature by withdrawing it from said chamber at a point substantially remote from the point at which the said heated oil is introduced into said chamber, passing the withdrawn oil in a flowing stream through an independent heating zone, and re- -turning it to said chamber at a point substantially remote from the point at which the heated oil is introduced from said first named heating zone and the point at which said oil is withdrawn from said charn 5. In apparatus for the conversion of high boiling oils into low boiling hydrocarbon oils such as gasoline, under pressure, a heating coil, means for forcing oil therethrough, an'enlarged chamber into which the heated oil from said coil is discharged, said chamber adapted to maintain in a body the oil discharged thereinto, an auxiliary heating coil, means for applying heat thereto, means for passing oil from the said body of oil in said enlarged chamber in an independent stream through the auxiliary heating coil and back to the said oil body in said enlarged chamber in an independent stream at a point remote from the point the heated oil is discharged thereinto from said first named heating coil.

6. In apparatus for the conversion of high boiling oils into low boiling hydrocarbon oils such as gasoline, under pressure, a heating coil, means for forcing oil therethrough, an enlarged chamber into which the heated oil from said coil is discharged in which said oil is maintained in a body, and auxiliary heating coil, means for applying heat thereto, means for passing oil from the said oil body maintained in the said enlarged chamber through the auxiliary heating coil and back to the said oil body in said enlarged chamber in an. independent stream at a point remote from the point the heated oil is discharged thereinto from said first named heating coil, whereby "the said oil body in the chamber may be maintained at the desired temperature, and means for withdrawing vapors from the enlarged chamber.

WILLIAM E. WARWICK.

CER'IlFiCATE m ceRiiemioN.

Patent No. 1,920,331. August 1, i933.

WiLLiAM E. WARWICK.

ii: is hereby certified iiiat ei's'or appears in the printed specification of the aimve numbered patent requiring eori'eetieii LES follows: Page 2, line 31, claim 2, for "there upeii" read "thei'eapeii"; line 105, claim 5, after "chamber" insert "being"; line Hi8, after "0i!" seeenai eecurrence insert "maintained"; line 109, before "said" insert "the"; anii iiiie iii, ior "oil bcdy" read "body 0i oil"; line 120, claim 6, beiore "in insert "and"; and line 121, for "and" real "an"; and ihat iiie said Letters Patent should i & read with these eorrections there in that the same may cenierm to the record (if the case in the Patent Office.

Signed and sealed this 19th day 0f Sepiember, A. D. 1933.

I M. J. Moore. (Seal) Acting Commissioner of Patents. 

